1. Field of the Invention
The present invention relates generally to a handwriting recognition and automatic character input method, and more particularly, to an apparatus for allowing a user to handwrite desired information in a defined area on a touch screen and automatically recognizing the information, and a method thereof.
2. Description of the Related Art
Mobile terminals include enhanced features along with the development of all related technologies, including a wired/wireless communication technology, a multimedia technology, a technology for manufacturing hardware such as Central Processing Units (CPUs) and memories, and a power charging technology. Because the conventional mobile terminals have been used mainly for calls, users have felt little inconvenience even though the terminals have only numeric keypad buttons corresponding to phone numbers. However, owing to the increasingly widespread use of text messages, users may be inconvenienced by having to input various types of languages and characters.
Due to the development of mobile terminal-related technology, the existing products such as Personal Digital Assistants (PDAs) and laptop computers, and also many new-concept products including smart phones, Netbooks, Mobile Internet Devices (MIDs) and Ultra Mobile PCs (UMPCs) have been launched. Thanks to the advances in such technologies, it is possible to run a variety of applications in the mobile terminals, which requires a quick and convenient character input method.
The current representative character input methods include a character input method using physical keypad buttons, a character input method using a virtual keypad on a touch screen, and a character input method of recognizing information handwritten on a touch screen. The three different character input methods will be described in detail below.
FIG. 1 illustrates the conventional character input method using physical keypad buttons.
Referring to FIG. 1, a screen for inputting text messages by a user can be displayed on an information display area 101. The mobile terminal includes a key button area 103 with multiple key buttons capable of inputting information, the information display area 101 for outputting a variety of information such as input characters or numbers and special characters, and multiple menu key buttons 105 and 107. A function capable of selecting Hangul, English, numbers and special characters may be included not only in a menu key button but also in a preset button, and the user can input desired characters by pressing associated keys with characters printed on them in the key button area 103. The user can compose desired text messages using the above structures.
FIG. 2 illustrates the conventional character input method using a virtual keypad on a touch screen.
Referring to FIG. 2, the touch screen can display a particular screen or an input screen with a virtual keypad by user input. A message input screen displayed on a touch screen 201 includes a key button area 203 with multiple key buttons capable of inputting information, a special key area 205 with multiple key buttons capable of selecting Hangul, English, numbers and special characters, an information display area 207 for outputting a variety of information such as characters or numbers and special characters being input by touches, and multiple menu key buttons 209 and 211.
In the case of the message input screen shown in FIG. 2, the same environment as the environment of composing messages using the physical keypad buttons shown in FIG. 1 may be implemented on the touch screen. Hence, the user can compose messages in the same way as the method of composing messages using the physical keypad buttons, with use of the key button area 203, the special key area 205 and the information display area 207, all of which are displayed on the touch screen 201.
FIG. 3 illustrates the conventional character input method using handwriting recognition on a touch screen.
Referring to FIG. 3, a touch screen 301 can display a particular screen by user input, i.e., can display an input screen different from the input screen with a virtual keypad shown in FIG. 2. A message input screen displayed on the touch screen 301 includes special key areas 303 with multiple key buttons capable of selecting Hangul, English, numbers and special characters, a handwriting recognition area 305 for directly inputting information using a finger or a stylus pen, an information display area 307 for outputting a variety of information such as characters or numbers and special characters being input by touch, and multiple menu key buttons 309 and 311.
In the message input screen shown in FIG. 3, the handwriting recognition area 305 includes three single-recognition areas for recognizing one character or number and special character at a time, and user desired information is displayed on the information display area 307 in the order that the information is input by an input tool, e.g. a finger or a stylus pen. To switch from Hangul to English, or from Hangul to other characters or numbers and special characters, the user may choose a predefined button in the special key areas 303 and then enter desired characters. Thus, the user may compose messages as if writing on a notebook by hand, using the information display area 307, the menu key buttons 309 and 311, and the handwriting recognition area 305 displayed on the touch screen 301.
However, in the case of the character input method using physical keypad buttons, to change specific settings of the mobile terminal or to set application information through character entry, the user must navigate to a pertinent input window by pressing particular menu or search buttons. Due to the limited number of keypad buttons, multiple characters are assigned to each button even for the same language to allow the user to enter various characters, so the user must enter the buttons selectively or in combination. This character input method inconveniences users who want fast text input.
The character input method using a virtual keypad on the touch screen also suffers from space limitations similar to those of the character input method using the physical keypad buttons, since the virtual keypad must be placed in the touch screen. This character input method is not so different from the character input method using physical keypad buttons in terms of the inconvenience to the user. In addition, to change a type of characters (numbers, uppercase English, lowercase English, Hangul, special characters, etc.) in the input window, the user needs to press particular keys for the character type change, which inevitably decreases the input speed.
Compared with the character input method using keypad buttons, the character input method using handwriting recognition on the touch screen is advantageous in that it can input characters by recognizing patterns of handwriting the user has entered without using keypad buttons, contributing to saving the keypad space. However, this method also needs additional setting tasks to change the character type, and in order to correct some of the input information, the user must choose the information to be corrected on the touch screen, delete the selected information, and then input the desired information.